Document Type
Thesis - Open Access
Award Date
2023
Degree Name
Master of Science (MS)
Department / School
Agronomy, Horticulture, and Plant Science
First Advisor
Sutie Xu
Abstract
Sustainable management practices have been recognized to improve ecosystem functions such as productivity, soil health, and resilience. The impacts of livestock and cover crop integration as sustainable techniques on soil health, however, are not well studied in South Dakota cropping systems. This study was conducted at the Southeast Research Farm, South Dakota with objectives to evaluate the impacts of cover crops and livestock integration on (i) soil bio-chemical properties and (ii) soil pore characteristics and hydro-physical properties. The research site was established based on no-till corn (Zea mays L.)-soybean (Glycine max (L.) Merr.)-oat (Avena sativa L.) rotation systems in 2016. The experiment was a randomized complete block design with four replicates. Treatments include a complete combination of three management strategies (integrated cover-crop livestock system (ICLS), cover crop without grazing (CC), and no cover crop or grazing control (CNT)) and three crop phases (corn, soybean, oat). For the first objective, soil sampling was conducted from all nine treatments in two seasons, October 2021 (fall) and May 2022 (spring) at 0-10 cm. For the second objective, sampling was conducted by collecting intact soil cores at 0-10 and 10-20 cm in May 2018 in the corn phase under the three management strategies. Results showed the potential of ICLS and CC in improving soil health. Total organic carbon and total nitrogen were increased under ICLS (30.3 and 2.51 g kg-1, respectively) and CC (30.4 and 2.56 g kg-1, respectively) compared to CNT (28 and 2.29 g kg-1, respectively). In Spring, soil microbial communities such as gram-positive bacteria, gram negative bacteria, actinomycetes and total fungi were promoted in oat phase under ICLS and were the lowest in soybean phase under CNT. Soil hydrophysical properties were also improved by CC or ICLS management, such as the increased number of pores, coarse mesoporosity and saturated hydraulic conductivity and decreased bulk density compared to those under CNT. Some other biological and hydro-physical characteristics, however, were regulated by seasons or crop phases rather than management. Thus, long-term study is necessary to further understand the soil health influenced by CC and ICLS in cropping systems under similar climate conditions and crop rotation strategies.
Library of Congress Subject Headings
Cropping systems -- South Dakota.
Soils -- Quality.
Cover crops.
Integrated agricultural systems -- South Dakota.
Grazing.
Livestock.
Publisher
South Dakota State University
Recommended Citation
Ghimire, Namrata, "Soil Health Influenced by Livestock and Cover Crops Integration in Row Cropping Systems in South Dakota" (2023). Electronic Theses and Dissertations. 692.
https://openprairie.sdstate.edu/etd2/692
Rights Statement
